Refuse containers which are rollable as by residential users to a position accessible for automatic dumping are increasing in popularity. The cost of auxiliary equipment which is necessitated, as well as the manual labor incident to the use thereof is also increasing. Hydraulic dumping apparatus carried by the garbage truck has been expensive due to complex linkage mechanisms. The receptacles are normally positioned by placing an upper bar into a receiving mechanism carried by the hydraulic dumping apparatus on a substantially vertical or upright carriage, and a latching mechanism carried by the carriage engages a lower latching bar positioned below the first mentioned upper bar carried by the receptacle. Such an apparatus is illustrated in U.S. Pat. Nos. 3,804,277 and 3,894,642. In such apparatus not only is the linkage for raising the receptable complicated, but the latching mechanism is not sufficiently positive.
Another typical example is that manufactured by Zarn, Inc., Post Office Box 1350, Reidsville, N.C. 27320, which employs a manually controlled hydraulic circuit such as is schematically illustrated herein for use with apparatus constructed in accordance with the present invention. The Zarn apparatus, as in most prior art systems, employs a continuously movable latch mechanism and employs a positive action at all times during the lowering of the receptacle which results in damage to the receptacle or hydraulic mechanism should an obstruction such as a rock, be encountered by the receptacle while it is being lowered. Since movement of the latch continues during the lifting, the latch or hook overtravels in order to achieve the necessary hooking action. The invention hereof is an improvement upon the current hydraulic or automatic dumping mechanisms.
Accordingly, it is an important object of this invention to provide positive and increased lifting power through sequentially operated linkage.
Another important object of the invention is to provide a positive latching means for fixing the receptacle with respect to the lifting and tilting carriage by securing a positive motion which occurs earlier in the lifting cycle and which is provided with lost motion means for eliminating overtravel of the securing hook.
Another important object of the invention is to provide a lifting mechanism which incorporates a safety feature to prevent damage to the receptacle by discontinuing the lifting linkage from the cylinder so that if the receptacle meets resistance on its downward cycle, the lifting carriage will merely pivot freely avoiding damage to the can or mechanism.